Incomplete Documentation No Support=Useless Plugin

I tried to use this plugin to generate a list, on a regular page, of posts within a single category. I’m not a high-end developer, neither am I a newbie. The only documentation I could find was in the readme.txt that came with the plugin, which for this function says to insert the shortcode:
[category-posts]

Of course, that doesn’t work because nothing indicates the actual category. I tried substituting an actual category name, but that didn’t work. Tried all sorts of things, and thoroughly searched in Google for some discussion. Since the author does not offer support, I was pretty much dead in the water with only wasted time to show for it. Too bad.